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Main articles: Navigation

Main articles: Radar

Marine radar systems can provide very useful navigation information in a variety of situations. When the vessel is within radar range of land or special radar aids to navigation, the navigator can take distances and angular bearings to charted objects and use these to establish arcs of position and lines of position on a chart.^[1] A fix consisting of only radar information is called a radar fix.^[2]
Some types of radar fixes include the relatively self-explanatory methods of "range and bearing to a single object,"^[3] "two or more bearings," "tangent bearings," and "two or more ranges."
Parallel indexing is a technique defined by William Burger in the 1957 book ''The Radar Observer's Handbook''.National Imagery and Mapping Agency, 2001:169. This technique involves creating a line on the screen that is parallel to the ship's course, but offset to the left or right by some distance. This parallel line allows the navigator to maintain a given distance away from hazards.
Some techniques have been developed for special situations. One, known as the "contour method," invloves marking a transparent plastic template on the radar screen and moving it to the chart to fix a position.National Imagery and Mapping Agency, 2001:164.
Another special technique, known as the Franklin Continuous Radar Plot Technique, involves drawing the path a radar object should follow on the radar display if the ship stays on its planned course.National Imagery and Mapping Agency, 2001:182. During the transit, the navigator can check that the ship is on track by checking that the pip lies on the drawn line.

Contents

See also

Notes

References

See also

★ Air navigation

★ Astrogation

★ Austronesian navigation

★ Galileo positioning system

★ Geodetic system

★ Great-circle distance explains how to find that quantity if one knows the two latitudes and longitudes.

★ Marshall Islands stick chart

★ Off-course navigation

★ Polynesian navigation

★ Franz Xaver, Baron Von Zach, a scientific editor and astronomer, first located many places geographically.

Notes

1. Maloney, 2003:744.
2. Bowditch, 2002:816.
3. National Imagery and Mapping Agency, 2001:163.

References

★ The American Practical Navigator, , Nathaniel, Bowditch, National Imagery and Mapping Agency, 2002,

★ Dutton's Nautical Navigation, , Thomas J., Cutler, Naval Institute Press, 2003,

★ Air Navigation, Department of the Air Force, , , Department of the Air Force, 2001,

★ Admiralty Manual of Seamanship, , , Great Britain Ministry of Defence (Navy), The Stationery Office, 1995,

★ Chapman Piloting and Seamanship, , Elbert S., Maloney, Hearst Communications Inc., 2003,

★ Publication 1310: Radar Navigation and Maneuvering Board Manual, National Imagery and Mapping Agency, , , U.S. Government Printing Office, 2001,